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How to pass a variable to a method of an extended class

I am extending the class ClassVisitor and overriding the method visitMethod. Then I extend the MethodVisitor and override the visitMethodInsn. When I override the visitMethod I create a new instance of the extended MethodVisitor.
Please see the code below to understand. Keep in mind knowledge of the ASM library is required in order to understand it properly.
GraphClass.java:
public class GraphClass extends ClassVisitor {
public GraphClass() {
super(ASM5);
}
public MethodVisitor visitMethod(int access, String name, String desc, String signature, String[] exceptions) {
System.out.println("testing " + name + desc);
GraphMethod newVisitor = new GraphMethod();
return newVisitor;
}
}
GraphMethod.java:
public class GraphMethod extends MethodVisitor{
public GraphMethod() {
super(ASM5);
}
public void visitMethodInsn(int opcode, java.lang.String owner, java.lang.String name, java.lang.String descriptor, boolean isInterface) {
System.out.println(owner + name);
}
}
What I am trying to do is pass the name variable from visitMethod to be printed along with the other variables in the visitMethodInsn.
I am new to Java, so any tips would be very helpful.

Based on the comments I will assume that you want to know which methods call by methods of the visited class, all right?
It takes solved easy by using tree-api of objectweb asm.
ClassReader cr = new ClassReader(bytesOfSomeClass);
//Used class node instead of visiter
ClasaNode cn = new ClassNode(<asm version>);
cr.accept(cn, 0);
//Iterate all methods of class
cn.methods.forEach( (MethodNode mn) -> {
String callerName = mn.name;
//Iterate all instructions of current method
Stream.iterate(mn.instructions.getFirst(), AbstractInsnNode::getNext).limit(instructions.size())
.filter(node -> node instanceof MethodInsnNode) //take only method calls
.forEach(node -> {
String calledName = ((MethodInsnNode) node).name;
//Print results
System.out.println(calledName + " is called by " + callerName);
});
});

Replacing if else statement with pattern

I have a if else statement which might grow in the near future.
public void decide(String someCondition){
if(someCondition.equals("conditionOne")){
//
someMethod("someParameter");
}else if(someCondition.equals("conditionTwo")){
//
someMethod("anotherParameter");
}
.
.
else{
someMethod("elseParameter");
}
}
Since, this is already looking messy, I think it would be better if I can apply any design patterns here. I looked into Strategy pattern but I am not sure if that will reduce if else condition here. Any suggestions?

This is a classic Replace Condition dispatcher with Command in the Refactoring to Patterns book.
Basically you make a Command object for each of the blocks of code in your old if/else group and then make a Map of those commands where the keys are your condition Strings
interface Handler{
void handle( myObject o);
}
Map<String, Handler> commandMap = new HashMap<>();
//feel free to factor these out to their own class or
//if using Java 8 use the new Lambda syntax
commandMap.put("conditionOne", new Handler(){
void handle(MyObject o){
//get desired parameters from MyObject and do stuff
}
});
...
Then instead of your if/else code it is instead:
commandMap.get(someCondition).handle(this);
Now if you need to later add new commands, you just add to the hash.
If you want to handle a default case, you can use the Null Object pattern to handle the case where a condition isn't in the Map.
Handler defaultHandler = ...
if(commandMap.containsKey(someCondition)){
commandMap.get(someCondition).handle(this);
}else{
defaultHandler.handle(this);
}

Let's assume that we have such code (which is the same as yours):
public void decide(String someCondition) {
if(someCondition.equals("conditionOne")) {
someMethod("someParameter");
}
else if(someCondition.equals("conditionTwo")) {
someMethod("anotherParameter");
}
else {
someMethod("elseParameter");
}
}
Assuming that you don't want to refactor other parts of the application and you don't want to change method signature there are possible ways in which it could be refactored:
Warning - You should use generic versions of mentioned patterns.
I showed non generic ones because it is easier to read them.
Strategy + Factory Method
We can use Strategy and Factory Method patterns. We also take advantage of polymorphism.
private final StrategyConditionFactory strategyConditionFactory = new StrategyConditionFactory();
public void decide(String someCondition) {
Strategy strategy = strategyConditionFactory.getStrategy(someCondition)
.orElseThrow(() -> new IllegalArgumentException("Wrong condition"));
strategy.apply();
}
It would be better to design it in a way that else condition is included in the factory, and developer calls it on purpose. In such case we throw exception when condition is not meet. Alternatively we could write it exactly as it was in question. If you want so instead of .orElseThrow(() -> new IllegalArgumentException("Wrong condition")); put .orElse(new ElseStrategy());
StrategyConditionFactory (factory method):
public class StrategyConditionFactory {
private Map<String, Strategy> conditions = new HashMap<>();
public StrategyConditionFactory() {
conditions.put("conditionOne", new ConditionOneStrategy());
conditions.put("conditionTwo", new ConditionTwoStrategy());
//It is better to call else condition on purpose than to have it in the conditional method
conditions.put("conditionElse", new ElseStrategy());
//...
}
public Optional<Strategy> getStrategy(String condition) {
return Optional.ofNullable(conditions.get(condition));
}
}
Strategy interface:
public interface Strategy {
void apply();
}
Implementations:
public class ConditionOneStrategy implements Strategy {
#Override
public void apply() {
//someMethod("someParameter");
}
}
public class ConditionTwoStrategy implements Strategy {
#Override
public void apply() {
//someMethod("anotherParameter")
}
}
public class ElseStrategy implements Strategy {
#Override
public void apply() {
//someMethod("elseParameter")
}
}
Usage (simplified):
public void strategyFactoryApp() {
//...
decide("conditionOne");
decide("conditionTwo");
decide("conditionElse");
//...
}
Strategy + Factory Method - this particular case (where only parameter changes)
We can use the fact that in this case we always call the same method, only parameter changes
We change our base strategy interface to abstract class with getParameter() method and we make new implementations of this abstract class. Other code remains the same.
public abstract class Strategy {
public abstract String getParameter();
public void apply() {
someMethod(getParameter());
}
private void someMethod(String parameter) {
//someAction
}
}
Implementations:
public class CondtionOneStrategy extends Strategy {
#Override
public String getParameter() {
return "someParameter";
}
}
public class CondtionTwoStrategy extends Strategy {
#Override
public String getParameter() {
return "anotherParameter";
}
}
public class ElseStrategy extends Strategy {
#Override
public String getParameter() {
return "elseParameter";
}
}
Enum + enum kinda "factory"
We might use Enum to implement strategy and instead of factory method we can use valueOf() from enum.
public void decide(String someCondition) {
ConditionEnum conditionEnum = ConditionEnum.valueOf(someCondition);
conditionEnum.apply();
}
Condition enum:
public enum ConditionEnum {
CONDITION_ONE {
#Override
public void apply() {
//someMethod("someParameter");
}
},
CONDITION_TWO {
#Override
public void apply() {
//someMethod("anotherParameter");
}
},
CONDITION_ELSE {
#Override
public void apply() {
//someMethod("elseParameter");
}
};
//...more conditions
public abstract void apply();
}
Usage (simplified):
public void enumFactoryApp() {
//...
decide("CONDITION_ONE");
decide("CONDITION_TWO");
decide("CONDITION_ELSE");
//...
}
Notice that you will get IllegalArgumentException when enum type has no constant with the specified name.
Command + Factory
The difference between strategy and command is that command holds also state, so if you have for example compute(int a, int b, String someCondition) and you want to refactor it with strategy including it's signature change you can reduce it to compute(int a, int b, ComputeStrategy computeStrategy) with command you can reduce it to one argument compute(ComputeCommand computeCommand). In this case we also take advantage of polymorphism similarly to strategy pattern case.
CommandConditionFactory commandConditionFactory = new CommandConditionFactory();
public void decide(String someCondition) {
Command command = commandConditionFactory.getCommand(someCondition)
.orElseThrow(() -> new IllegalArgumentException("Wrong condition"));
command.apply();
}
It would be better to design it in a way that else condition is included in the factory, and developer calls it on purpose. In such case we throw exception when condition is not meet. Alternatively we could write it exactly as it was in question. If you want so instead of .orElseThrow(() -> new IllegalArgumentException("Wrong condition")); put .orElse(new ElseCommand());
CommandConditionFactory (factory method):
public class CommandConditionFactory {
private Map<String, Command> conditions = new HashMap<>();
public CommandConditionFactory() {
conditions.put("conditionOne", new ConditionOneCommand("someParameter"));
conditions.put("conditionTwo", new ConditionTwoCommand("anotherParameter"));
//It is better to call else condition on purpose than to have it in the conditional method
conditions.put("conditionElse", new ElseCommand("elseParameter"));
//...
}
public Optional<Command> getCommand(String condition) {
return Optional.ofNullable(conditions.get(condition));
}
}
Command interface:
public interface Command {
void apply();
}
Implementations (there is some redundancy, but It is there to show how command should look in more general case where instead of someMethod() we have three different methods):
public class ConditionOneCommand implements Command {
private final String parameter;
public ConditionOneCommand(String parameter) {
this.parameter = parameter;
}
#Override
public void apply() {
//someMethod(parameter);
}
}
public class ConditionTwoCommand implements Command {
private final String parameter;
public ConditionTwoCommand(String parameter) {
this.parameter = parameter;
}
#Override
public void apply() {
//someMethod(parameter);
}
}
public class ElseCommand implements Command {
private final String parameter;
public ElseCommand(String parameter) {
this.parameter = parameter;
}
#Override
public void apply() {
//someMethod(parameter);
}
}
Usage (simplified):
public void commandFactoryApp() {
//...
decide("conditionOne");
decide("conditionTwo");
decide("conditionElse");
//...
}
Command + Factory - This particular case.
This in fact isn't a real command pattern just a derivative. It takes advantage of the fact that in this case we are always calling the same method someMethod(parameter) and only the parameter changes.
Abstract class:
public abstract class Command {
abstract void apply();
protected void someMethod(String parameter) {
//someAction
}
}
Implementation (the same for all 3 conditional cases):
public class CommandImpl extends Command {
private final String parameter;
public CommandImpl (String parameter) {
this.parameter = parameter;
}
#Override
public void apply(){
someMethod(parameter);
}
}
Factory, please notice that there is only one command implementation, only parameter changes:
public class CommandConditionFactory {
Map<String, Command> conditions = new HashMap<>();
public CommandConditionFactory() {
conditions.put("conditionOne", new CommandImpl("someParameter"));
conditions.put("conditionTwo", new CommandImpl("anotherParameter"));
//It is better to call else condition on purpose than to have it in the conditional method
conditions.put("conditionElse", new CommandImpl("elseParameter"));
//...
}
public Optional<Command> getCommand(String condition) {
return Optional.ofNullable(conditions.get(condition));
}
}
Nested if's
Note that even if you have nested ifs sometimes it is possible to refactor them and use one of the mentioned techniques.
Lets say that we have following code:
public void decide2(String someCondition, String nestedCondition) {
if(someCondition.equals("conditionOne")) {
if(nestedCondition.equals("nestedConditionOne")){
someLogic1();
}
else if(nestedCondition.equals("nestedConditionTwo")){
someLogic2();
}
}
else if(someCondition.equals("conditionTwo")) {
if(nestedCondition.equals("nestedConditionThree")){
someLogic3();
}
else if(nestedCondition.equals("nestedConditionFour")){
someLogic4();
}
}
}
You could refactor it using mathematical logic rules:
public void decide2(String someCondition, String nestedCondition) {
if(someCondition.equals("conditionOne")
&& nestedCondition.equals("nestedConditionOne")) {
someLogic1();
}
else if(someCondition.equals("conditionOne")
&& nestedCondition.equals("nestedConditionTwo")) {
someLogic2();
}
else if(someCondition.equals("conditionTwo")
&& nestedCondition.equals("nestedConditionThree")) {
someLogic3();
}
else if(someCondition.equals("conditionTwo")
&& nestedCondition.equals("nestedConditionFour")) {
someLogic4();
}
}
and then you can use strategy, enum or command. You just have a pair of Strings <String, String> instead of single String.
Decision Tables
When you have nested ifs that couldn't be refactored as mentioned you can implement your own decision tables or use some ready to go decision tables solution. I won't give the implementation there.
Rules Engine
When you have nested ifs that couldn't be refactored as mentioned you can also implement your own simple rules engine. You should use it only if you have many nested ifs, otherwise it is triumph of form over content.
For very complicated Business Logic there are professional Rule Engines like Drools.
I won't give the implementation there.
One more thing
In the example that you gave there is a high possibility that someone introduced these ifs, but they are totally redundant. And we can check it by trying to refactor decide method signature to make it take some other argument and to refactor surrounding code that is calling our method. By doing so we are getting rid of our Factory Method. There are examples that present how the code might look when it occurs that these ifs were redundant.
Strategy
Decide method:
public void decide(Strategy strategy) {
strategy.apply();
}
Usage (simplified):
public void strategyApp() {
//...
decide(new ConditionOneStrategy());
decide(new ConditionTwoStrategy());
decide(new ElseStrategy());
//...
}
Enum
Decide method:
public void decide(ConditionEnum conditionEnum) {
conditionEnum.apply();
}
Usage (simplified):
public void enumApp() {
//...
decide(ConditionEnum.CONDITION_ONE);
decide(ConditionEnum.CONDITION_TWO);
decide(ConditionEnum.CONDITION_ELSE);
//...
}
Command
Decide method:
public void decide(Command command) {
command.apply();
}
Usage (simplified):
public void commandApp() {
//...
decide(new ConditionOneCommand("someParameter"));
decide(new ConditionTwoCommand("anotherParameter"));
decide(new ElseCommand("elseParameter"));
//...
}
In fact it is quite specific case, there are cases in which for example we have to use simple type like String, because it comes from the external system or condition is based on integer from input so we can't refactor the code so easily.

The general recommendation by Martin Fowler is to
Replace Conditional with Polymorphism.
In terms of design patterns this would often be the Strategy Pattern
Replace Conditional Logic with Strategy.
If you have a small, finite set of conditions, I recommend to use an enum to implement the Strategy Pattern (provide an abstract method in the enum and override it for each constant).
public enum SomeCondition{
CONDITION_ONE{
public void someMethod(MyClass myClass){
//...
}
},
CONDITION_TWO{
public void someMethod(MyClass myClass){
}
}
public abstract void someMethod(MyClass myClass);
}
public class MyClass{
//...
public void decide(SomeCondition someCondition){
someCondition.someMethod(this);
}
}
If it's really just a parameter you want to pick, then you could define the enum like this instead:
public enum SomeCondition{
CONDITION_ONE("parameterOne"),
CONDITION_TWO("parameterTwo");
private final String parameter;
private SomeCondition(String parameter){
this.parameter = parameter;
}
public String getParameter(){
return parameter;
}
}
public class MyClass{
//...
public void decide(SomeCondition someCondition){
someMethod(someCondition.getParameter());
}
}

Another way to solve the current problem is to use Factory Pattern. This provides functionality to extract a factory method that returns an object of a given type and performs the operation based on the concrete object behavior.
public interface Operation {
String process(String a, String b);
}
The method takes two string as input and returns the result.
public class Concatenation implements Operation {
#Override
public String process(String a, String b) {
return a.concat(b);
}
}
public class Join implements Operation {
#Override
public String process(String a, String b) {
return String.join(", ", a, b);
}
}
And then we should define a factory class which returns instances of Operation based on the given operator:
public class OperatorFactory {
static Map<String, Operation> operationMap = new HashMap<>();
static {
operationMap.put("concatenation", new Concatenation());
operationMap.put("join", new Join());
// more operators
}
public static Optional<Operation> getOperation(String operator) {
return Optional.ofNullable(operationMap.get(operator));
}
}
And now we can use it:
public class SomeServiceClass {
public String processUsingFactory(String a, String b, String operationName) {
Operation operation = OperatorFactory
.getOperation(operationName)
.orElseThrow(() -> new IllegalArgumentException("Invalid Operation"));
return operation.process(a, b);
}
}

I guess you must have already considered it, but if you are using JDK 7 or above, you can switch on strings. That way your code can look cleaner than a bunch of if-else statements.

How to modify a Java bytecode using ASM 4.0

I am new to ASM framework. I have been working around this ASM framework for a week. I saw tutorials in net regarding parsing a class and Generating a .class file from scratch.
But am unable to follow how to modify a existing class in ASM.
I am unable to follow the flow of execution between the ClassVisitor, ClassWriter and ClassReader.
Kindly solve my issue by giving me a ASM example for the following code.
public class ClassName {
public void showOne() {
System.out.println("Show One Method");
}
public static void main(String[] args) {
ClassName c = new ClassName();
c.showOne();
}
}
The above class should be modified as:
public class ClassName {
public void showOne() {
System.out.println("Show One Method");
}
public void showTwo() { // <- Newly added method
System.out.println("Show Two Method");
}
public static void main(String[] args) {
ClassName c = new ClassName();
c.showOne();
c.showTwo(); // <- Newly inserted method call
}
}
What should be the ASM code to modify it?
I used the ASMifier tool to generate the code. But I don't know where to apply it.

Your requirements are a bit underspecified. Below is an example program which uses ASM’s visitor API for transforming a class assumed to have the structure of your question to the resulting class. I added a convenience method taking a byte array and returning a byte array. Such a method can be used in both cases, a static transformation applied to class files on disk as well as in an Instrumentation agent.
When combining a ClassWriter with a ClassVisitor passed to a ClassReader as below, it will automatically replicate every feature of the source class so you have to override only these methods where you want to apply changes.
Here, visitMethod is overridden to intercept when encountering the main method to modify it and visitEnd is overridden to append the entirely new showTwo method. The MainTransformer will intercept RETURN instructions (there should be only one in your example) to insert the call to showTwo before it.
import org.objectweb.asm.*;
import org.objectweb.asm.commons.GeneratorAdapter;
public class MyTransformer extends ClassVisitor {
public static byte[] transform(byte[] b) {
final ClassReader classReader = new ClassReader(b);
final ClassWriter cw = new ClassWriter(classReader,
ClassWriter.COMPUTE_FRAMES|ClassWriter.COMPUTE_MAXS);
classReader.accept(new MyTransformer(cw), ClassReader.EXPAND_FRAMES);
return cw.toByteArray();
}
public MyTransformer(ClassVisitor cv) {
super(Opcodes.ASM5, cv);
}
#Override
public MethodVisitor visitMethod(int access, String name, String desc,
String signature, String[] exceptions) {
MethodVisitor v=super.visitMethod(access, name, desc, signature, exceptions);
if(name.equals("main") && desc.equals("([Ljava/lang/String;)V"))
v=new MainTransformer(v, access, name, desc, signature, exceptions);
return v;
}
#Override
public void visitEnd() {
appendShowTwo();
super.visitEnd();
}
private void appendShowTwo() {
final MethodVisitor defVisitor = super.visitMethod(
Opcodes.ACC_PUBLIC, "showTwo", "()V", null, null);
defVisitor.visitCode();
defVisitor.visitFieldInsn(Opcodes.GETSTATIC,
"java/lang/System", "out", "Ljava/io/PrintStream;");
defVisitor.visitLdcInsn("Show Two Method");
defVisitor.visitMethodInsn(Opcodes.INVOKEVIRTUAL,
"java/io/PrintStream", "println", "(Ljava/lang/String;)V", false);
defVisitor.visitInsn(Opcodes.RETURN);
defVisitor.visitMaxs(0, 0);
defVisitor.visitEnd();
}
class MainTransformer extends GeneratorAdapter
{
MainTransformer(MethodVisitor delegate, int access, String name, String desc,
String signature, String[] exceptions) {
super(Opcodes.ASM5, delegate, access, name, desc);
}
#Override
public void visitInsn(int opcode) {
if(opcode==Opcodes.RETURN) {
// before return insert c.showTwo();
super.visitVarInsn(Opcodes.ALOAD, 1); // variable c
super.visitMethodInsn(Opcodes.INVOKEVIRTUAL,
"ClassName", "showTwo", "()V", false);
}
super.visitInsn(opcode);
}
}
}

Intellij IDEA plugin - PersistentStateComponent loadState not called

I am trying to develop a plugin for Intellij IDEA, I am working with SDK 129.451.
The issue I have is that I can't persist the user data like some list items he can input in the plugin and have the data back after the IDE restarts..
I am using PersistentStateComponent to persist the data, the getState() method seems to be called but the loadState() method doesn't.
Here is a sample class that extends PersistentStateComponent:
#State(name = "Test", storages = {#Storage(file = StoragePathMacros.APP_CONFIG+"/other.xml"
)})
public class Test implements PersistentStateComponent<Element> {
String ceva;
public Test() {
ceva = "sad";
System.out.println("constr");
}
public String getCeva() {
return ceva;
}
public void setCeva(String ceva) {
this.ceva = ceva;
}
public void loadState(Element state) {
System.out.println("cstate load");
ceva = (String) state.getContent().get(0);
}
public Element getState() {
System.out.println("cstate retu");
Element configurationsElement = new Element("testtt");
configurationsElement.addContent(ceva);
return configurationsElement;
}
}
Also I added this class in plugin.xml here:
<extensions defaultExtensionNs="com.intellij">
<applicationService serviceImplementation="ro.catalin.prata.testflightuploader.controller.Test"/>
<!-- Add your extensions here -->
<toolWindow id="TF Uploader" secondary="true" icon="/general/add.png" anchor="right"
factoryClass="ro.catalin.prata.testflightuploader.view.TFUploader">
</toolWindow>
</extensions>
And I also have a tool window class:
public class TFUploader implements ToolWindowFactory {
private JButton buttonAction;
private ToolWindow myToolWindow;
final Test test = ServiceManager.getService(Test.class);
public TFUploader() {
// I assume it should print the saved string but it doesn't
System.out.println(test.getCeva());
buttonAction.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
// if I click a button I am setting some new value to the string I want to save
test.setCeva(test.getCeva() + "-dddddd+");
}
});
}
Ok so, if I close the app or minimize it, the getState method gets called as I expected.. but when I open the app, the loadState method doesn't get called.. can somebody help me how I can solve this?
I already read this but it doesn't seem to help me to much. Also I want to use PersistentStateComponent as I want to save objects more complex than a simple String.
Thank you in advance!

Ok, I made it! :)
I don't know exactly what the issue was but I changed the Test class to this:
#State(
name = "Test", storages = {
#Storage(
id = "other",
file = "$APP_CONFIG$/testpersist.xml")
})
public class Test implements PersistentStateComponent<Test> {
String ceva;
public Test() {
ceva = "sad";
System.out.println("constr");
}
public String getCeva() {
return ceva;
}
public void setCeva(String ceva) {
this.ceva = ceva;
}
public void loadState(Test state) {
System.out.println("cstate load");
XmlSerializerUtil.copyBean(state, this);
}
public Test getState() {
System.out.println("cstate retu");
return this;
}
}
And in the TFUploader I changed the way I loaded the Test class to this:
final Test test = ServiceManager.getService(Test.class);
I hope it helps others..

I have already commented here but will say again that in my case loadState(MyService state) wasn't called because of lack of getter and setter for stateValue from this example:
class MyService implements PersistentStateComponent<MyService> {
public String stateValue;
public MyService getState() {
return this;
}
public void loadState(MyService state) {
XmlSerializerUtil.copyBean(state, this);
}
}

In my case I was getting a NullPointerException even before loadState was getting called. Similar to your code above I used an Element class as the state class. I had a constructor with some parameters in Element class. This was the problem as the framework could not create an instance of my state class. I tried to add a blank constructor without any parameters. This worked.

Pass outer anon class ref to a method in an inner anon class

How to pass outer anon class ref to a method in an inner anon class in Java?
I have a method that makes async call to a server - sendCall(some_args, callback). The callback is represented by anonymous class (let's name it OuterAnon) and contains a method for failure case. Inside this method a message box is created and sendCall() is called each time OK button is pressed. So I need to pass OuterAnon to the method again.
Here is a code to demonstrate what I mean:
private void sendCall(MyData data, OuterAnon<Boolean> callback){/*...*/}
private void myCall(final MyData data) {
sendCall(data, new OuterAnon<Boolean>() {
public void onFailure(Throwable throwable) {
final OuterAnon<Boolean> callback = this; //how to avoid this?
MessageBox.show(throwable.getMessage(), new MessageListener() {
public void process(MessageBox.OnClick action) {
if (action == MessageBox.OnClick.OK) {
sendCall(new MyData("resend?"), callback);
}
}
});
}
}
});
}
As you noticed, I take a ref for callback here:
final OuterAnon<Boolean> callback = this;
and use it here:
sendCall(new MyData("resend?"), callback);
But I want to avoid ref creation and pass callback like:
sendCall(new MyData("resend?"), this); //at the moment we point to MessageListener instead of OuterAnon.
Is there any way to do it in Java?

It's hard for us to fix since you've only shown incomplete code with classes that aren't supplied, so I don't know if this example is syntactically correct. That being said, a refactoring like this may suit your needs:
private void myCall(final MyData data)
{
sendCall(data, new OuterAnon<Boolean>()
{
public void onFailure(Throwable throwable)
{
showErrorMessage(throwable);
}
});
}
private void showErrorMessage(Throwable throwable)
{
MessageBox.show(throwable.getMessage(), new MessageListener()
{
public void process(MessageBox.OnClick action)
{
if (action == MessageBox.OnClick.OK)
{
sendCall(new MyData("resend?"));
}
}
});
}
private void sendCall(MyData data)
{
sendCall(data, this);
}
In general, I think it's a usually good idea to abstract code out of anon inner classes and into their own method on the enclosing class. It's now testable, reusable, and more readable, IMO.

If you really need to specify the onFailure inside the inner class the way you showed the code, and if you need to use that specific reference for callback, and you need to code this way...
Let's answer the question: no.
In my attempts, I've achieved 3 ways to access the anon-inner-least instance inside the anon-inner-most instance, but I think that none satisfies what you expect.
In that case, the anon-inner-most doesn't have a reference to the anon-inner-least: as you said, the this now points to the anon-inner-least.
Also, I tried to search at the java specification, but couldn't find exactly the answer to the question - if someone find the answer there, please contribute.
My try:
import java.util.ArrayList;
import java.util.LinkedList;
public abstract class AnonTest {
public static void main(String[] args) {
new ArrayList<Object>() {
private static final long serialVersionUID = -5986194903357006553L;
{
// initialize inner anon class
add("1");
}
// Way 1
private Object thisReference1 = this;
// Way 2
private Object getThisReference2() {
return this;
}
#Override
public boolean equals(Object obj) {
// Way 3
final Object thisReference3 = this;
new LinkedList<Object>() {
private static final long serialVersionUID = 900418265794508265L;
{
// initialize inner inner anon class
add("2");
}
#Override
public boolean equals(Object innerObj) {
// achieving the instance
System.out.println(thisReference1);
System.out.println(getThisReference2());
System.out.println(thisReference3);
System.out.println(this);
System.out.println();
// achieving the class
System.out.println(thisReference1.getClass());
System.out.println(getThisReference2().getClass());
System.out.println(thisReference3.getClass());
System.out.println(this.getClass());
System.out.println(this.getClass().getEnclosingClass());
return super.equals(innerObj);
}
}.equals("");
return super.equals(obj);
}
}.equals("");
}
}